This is a request for support of a Gordon Research Conference on Proteolytic Enzymes and Their Inhibitors. The objective of this conference is to bring together 31 international authorities in the field and to have them discuss current work, new directions and controversial issues before a critical audience of 100 or more experts from academic, industrial, and governmental institutions throughout the U.S. The subject is of great interest to a widely diversified group of biomedical and clinical investigators including immunologists, pharmacologists, hematologists, rheumatologists, reproductive physiologists and experimental pathologists interested in inflammation, vascular biology, connective tissue diseases, emphysema and cancer. Proteolytic events mediate cellular invasion which is critical to many important biologic processes including embryogenesis, ovulation and embryo- implantation, tissue repair, and tumor metastasis. Plasminogen activators and their naturally occurring inhibitors participate in vascular pathology, in cellular invasion, and in inflammatory cell function. New methodologies are appearing for creating artifical enzymes. Genetically engineered mutants of serine protease inhibitors have important therapeutic potential. The molecular biology and in vivo action of neutrophil proteases has been further defined. A better understanding of the mechanisms for the activation and inhibition of blood coagulation proteases has been achieved. All of these aspects, from the molecular biology to physiological and pathological functions of proteases and their inhibitors will be considered in this five-day conference (31 major speakers plus five poster session). The subject matter of the conference is of considerable importance to human health. PHS support would be consistent with the mission of the DHEW.